Add PR closed handler workflow

This workflow triggers when a pull request is closed, commenting on whether it was merged or not.

Author: dineshyr29-04

.github/workflows/pr-closed.yml

@@ -0,0 +1,31 @@
+name: PR Closed Handler
+
+on:
+  pull_request:
+    types: [closed]
+
+jobs:
+  on-close:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Comment on PR close
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const pr = context.payload.pull_request;
+
+            let message = "";
+
+            if (pr.merged) {
+              message = "🎉 PR merged successfully. Thanks for contributing!";
+            } else {
+              message = "❌ PR closed without merge. Please fix issues and try again.";
+            }
+
+            await github.rest.issues.createComment({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: pr.number,
+              body: message
+            });